• Title/Summary/Keyword: Damage Patterns

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Protective efficacies of Aronia melanocarpa (Blackberry) on the Allyl Alcohol-damaged Hepatocyte of Mice (쥐의 알코올성 간세포 손상에 대한 Aronia melanocapa(Blackberry)의 보호효과)

  • Han, Sang-Zin
    • Korean Journal of Pharmacognosy
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    • v.44 no.1
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    • pp.91-96
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    • 2013
  • The results of the alcohol decomposition ability of Aronia melanocarpa are as follows. Plasma alcohol concentration of the Aronia group was ca. 48.9% lower than the control group, but half an hour faster in that of Aronia before alcohol group, ca. 54.9% higher and half an hour later than that of the control group. ALDH(acetaldehyde dehydrogenase) of the Aronia group was ca. 243% higher than that of the control group. But maximal ALDH of the group taking Aronia before alcohol administration showed 0.5h faster and ca. 267% higher than that of the control group. This result shows that the activity of ALDH was increased by the Aronia. Aronia group's AST and ALT are increasing with similar patterns and their levels continually under the control's, but ca. 12.6% lower at AST and ca. 19.0% lower at ALT than those of control group. Ca. 21.7% lower at AST and ca. 40.5% lower at ALT in the Aronia group before alcohol administration than those of the control group. This result shows that Aronia has a role of suppressor against the liver damage. Therefore, this study proved lucidly the protective effects of Aronia on the hepatocyte.

Osmoregulation and mRNA Expression of a Heat Shock Protein 68 and Glucose-regulated Protein 78 in the Pacific oyster Crassostrea gigas in Response to Salinity Changes

  • Jo, Pil-Gue;Choi, Yong-Ki;An, Kwang-Wook;Choi, Cheol-Young
    • Journal of Aquaculture
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    • v.20 no.4
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    • pp.205-211
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    • 2007
  • Stress-inducible proteins may function in part as molecular chaperones, protecting cells from damage due to various stresses and helping to maintain homeostasis. We examined the mRNA expression patterns of a 68-kDa heat shock protein (HSP68) and 78-kDa glucose-regulated protein (GRP78) in relation to physiological changes in Pacific oyster Crassostrea gigas under osmotic stress. Expression of HSP68 and GRP78 mRNA in the gill significantly increased until 48 h in a hypersaline environment (HRE) and 72 h in a hyposaline environment (HOE), and then decreased. Osmolality and the concentrations of $Na^+$, $Cl^-$, and $Ca^{2+}$ in the hemolymph of HRE oysters significantly increased until 72 h (the highest value) and then gradually decreased; in HOE oysters, these values significantly decreased until 72 h (the lowest value), and then increased. These results suggest that osmolality and $Na^+$, $Cl^-$, and $Ca^{2+}$ concentrations were stabilized by HSP68 and GRP78, and indicate that these two stress-induced proteins play an important role in regulating the metabolism and protecting the cells of the Pacific oysters exposed to salinity changes.

The Electronic Laser Interferometry and Laser Heating Method for Residual Stress Determination

  • Kim, Koung-Suk;Kang, Young-June;Rho, Kyung-Wan;Ryu, Weon-Jae
    • Journal of Mechanical Science and Technology
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    • v.14 no.7
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    • pp.715-721
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    • 2000
  • Residual stress is one of the causes which makes defects in engineering components and materials. These residual stresses can occur in many engineering structures and can sometimes lead to premature failures. There are commonly used methods by which residual stresses are currently measured. But these methods have a little damage and other problems; therefore, a new experimental technique has been devised to measure residual stress in materials with a combination of electronic laser interferometry, laser heating and finite element method. The electronic laser interferometer measures in-plane deformations while the laser heating and cooling provides for very localized stress relief. FEM is used for determining the heat temperature and other parameters. The residual stresses are determined by the amount of strain that is measured subsequent to the heat-up and cool-down of the region being interrogated. A simple model is presented to provide a description of the method. In this paper, the ambiguity problem for the fringe patterns has solved by a phase shifting method.

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2-Chloroethylethyl Sulfide Induces Apoptosis and Necrosis in Thymocytes

  • Hur, Gyeung-Haeng;Kim, Yun-Bae;Shin, Sung-Ho
    • BMB Reports
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    • v.31 no.2
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    • pp.183-188
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    • 1998
  • 2-chloroethylethyl sulfide (CEES) is an alkylating agent that readily reacts with a wide variety of biological molecules causing metabolic abnormality. The mechanism of cell death during CEES injury is poorly understood. We have examined the effect of exposure of thymocytes with various concentrations of CEES to determine the pattern of cell death in thymocytes injury induced by CEES. In the present study, we show that two patterns of cell death occurred by either one of two mechanisms: apoptosis and necrosis. Exposure to low level of CEES (100 ${\mu}M$) for 5 h caused an induction of apoptosis on thymocytes, as identified by the following criteria: DNA fragmentation visualized by the characteristic "ladder" pattern was observed upon agarose gel electrophoresis and morphological features were revealed by microscopical observations. In contrast, exposure to high levels of CEES (500 ${\mu}M$) induce necrotic features such as cell lysis. Thus, depending on the concentrations, CEES can result in either apoptotic or necrotic cell damage. Our findings suggest that thymocytes which are not killed directly, but merely injured by low levels of CEES, are able to activate an internally-programmed cell death mechanism, whereas thymocytes receiving severe damages apparently can not.

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A Study on the Soluble Salt and Deterioration of Ceramics from Taean Shipwreck (태안 마도 출토 도자기의 염에 의한 손상상태 연구)

  • Jang, Sung-Yoon;Nam, Byeong-Jik;Park, Dae-Woo;Kang, Hyun-Mi;Jung, Yong-Hwa
    • 보존과학연구
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    • s.30
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    • pp.189-202
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    • 2009
  • Ceramics from Taean shipwreck were studied to investigate the deterioration by soluble salts and desalination pattern according to each ceramic characterization. NaCl crystals were found as a crystal growth on the ceramic microstructure and deteriorated to push off the glaze layer of some Puncheong ware sample. As a result of monitoring the desalination pattern of ceramics for 74days, the earthenware sample with big pores and no glaze removed soluble salts so fast, but Puncheong ware and Whiteware samples removed lots of soluble salts slowly and continuously. Generally, it takes long time to remove soluble salts from porcelains, due to small pores and glaze, but the long-term desalination probably can cause the damage on the surface layer such like glaze. As some soluble salts still remains in the ceramic microstructures after desalination, it is very important to control and keep the relative humidity stable through the proper storage. There are various ceramic deterioration patterns by soluble salts. Therefore, it needs to select the desalination method of ceramics from shipwreck, considering the material characteristics and the production techniques.

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A Study on the Development of Welding Clothes in Shipyards (조선소 용접복 개발에 관한 연구)

  • Kang, Hee-Chung;Choi, Hei-Sun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.8
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    • pp.1169-1178
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    • 2008
  • In this study, a questionnaire was compiled by conducting interviews and preliminary surveys, and then handed out to a total of 270 welders working in shipyards to investigate their opinions on welding clothes. By which investigation, it was intended to understand their dissatisfactions and issues with conventional welding clothes and then propose of such welding clothes as may offer better fit and suitability. A total of twenty welding suits were collected to find the locations and degrees of wear and tear. Due to too large differences in the locations and degrees of wear and tear among the clothes, the evaluation was focused on ten suits out of the twenty suits collected. The researcher’s subjective judgment was used to select the nineteen most severely damaged parts, which were then photographed in a uniform distance and evaluated by a group of experts in terms of the degree of damage in order to locate most severely damaged parts and select adequate materials for those parts in designing an experimental suit. Based on two above evaluations, the experimental welding suit was produced in consideration of the design, materials and patterns. A lab evaluation and a site evaluation were conducted to compare the experimental suit and other conventional suits, a lab evaluation and a field evaluation were performed.

A study on the adhesion of Ag film deposited on Alloy42 substrate (Alloy42 기판 위에 증착된 Ag막의 밀착력에 관한 연구)

  • 이철룡;천희곤;조동율;이건환;권식철
    • Journal of Surface Science and Engineering
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    • v.32 no.4
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    • pp.496-502
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    • 1999
  • Electroplating of Ag and Au on the functional area of lead frames are required for good bonding ability in IC packaging. As the patterns of the lead frame become finer, development of new deposition technology has been required for solving problems associated with process control for uniform thickness on selected area. Sputtering was employed to investigate the adhesion between substrate Alloy42 and Ag film as a new candidate process alternative to conventional electroplating. Coating thickness of Ag film was controlled to 3.5$\mu\textrm{m}$ at room temperature as a reference. The deposition of film was optimized to ensure the adhesion by process parameters of substrate heating temperature at $100~300^{\circ}C$, sputter etching time at -300V for 10~30min, bias voltage of -100~-500V, and existence of Cr interlayer film of $500\AA$. The critical $load L_{c}$ /, defined as the minimum load at which initial damage occurs, was the highest up to 29N at bias voltage of -500V by scratch test. AFM surface image and AES depth profile were investigated to analyze the interface. The effect of bias voltage in sputtering was to improve the surface roughness and remove the oxide on Alloy42.

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A Study on the Removal of Native Oxide on a Silicon Surface Using UV-Excited $F_2/H_2$ (UV-excited $F_2/H_2$를 이용한 실리콘 자연산화막 제거에 관한 연구)

  • Choi, S.H.;Choi, J.S.;Kim, S.I.;Koo, K.W.;Chun, H.G.
    • Proceedings of the KIEE Conference
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    • 1997.07d
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    • pp.1528-1530
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    • 1997
  • As device size shrinks, contamination will increasingly affect the reliability and yield of device. Therefore, contaminants must be removed from the surfaces of Si wafers prior to each process. But it becomes out increasingly difficult to clean silicon surfaces with finer patterns by the conventional wet treatment because of the viscosity and surface tension of solutions. Hence, a damage less dry cleaning process is needed for the silicon surfaces. For the removal of Si native oxide by UV-enhanced dry cleaning. $F_2$ gas and $F_2/H_2$ mixed gas were applied. As a result of analysis, UV-enhnaced $F_2/H_2$ treatment is more suitable than UV-enhanced $F_2$ treatment for removal of native oxide on the surfaces of Si wafers.

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Pharmaceuticals in Environment and Their Implication in Environmental Health (의약물질의 환경오염과 환경보건)

  • Choi, Kyung-Ho;Kim, Pan-Gyi;Park, Jeong-Im
    • Journal of Environmental Health Sciences
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    • v.35 no.6
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    • pp.433-446
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    • 2009
  • Pharmaceuticals in the aquatic environment are trace contaminants of growing importance in environmental health due to their physiologically active nature. Pharmaceuticals could affect non-target species and might eventually damage sustainability of susceptible populations in the ecosystem. Potentials for health consequences among susceptible human population cannot be ruled out since long-term exposure to cocktails of pharmaceuticals, which might be present in drinking water, is possible. Selection of antibiotic resistant microorganisms is of another concern. In order to understand, and if needed, to properly address the environmental health issues of pharmaceutical residues, knowledge gaps need to be filled. Knowledge gaps exist in many important areas such as prioritization of target pharmaceuticals for further risk studies, occurrence patterns in different environments, chronic toxicities, and toxicities of pharmaceutical mixtures. Appropriate treatment technologies for drinking water and wastewater could be developed when they are deemed necessary. One of the simplest, yet most efficient measures that could be undertaken is to implement a return program for unused or expired drugs. In addition, implementation of environmental risk assessment frameworks for pharmaceuticals would make it possible to efficiently manage potential environmental health problems associated with pharmaceutical residues in the environment.

Seismic performance evaluation of mid-rise shear walls: experiments and analysis

  • Parulekar, Y.M.;Reddy, G.R.;Singh, R.K.;Gopalkrishnan, N.;Ramarao, G.V.
    • Structural Engineering and Mechanics
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    • v.59 no.2
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    • pp.291-312
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    • 2016
  • Seismic performance evaluation of shear wall is essential as it is the major lateral load resisting member of a structure. The ultimate load and ultimate drift of the shear wall are the two most important parameters which need to be assessed experimentally and verified analytically. This paper comprises the results of monotonic tests, quasi-static cyclic tests and shake-table tests carried out on a midrise shear wall. The shear wall considered for the study is 1:5 scaled model of the shear wall of the internal structure of a reactor building. The analytical simulation of these tests is carried out using micro and macro modeling of the shear wall. This paper mainly consists of modification in the hysteretic macro model, developed for RC structural walls by Lestuzzi and Badoux in 2003. This modification is made by considering the stiffness degradation effect observed from the tests carried out and this modified model is then used for nonlinear dynamic analysis of the shear wall. The outcome of the paper gives the variation of the capacity, the failure patterns and the performance levels of the shear walls in all three types of tests. The change in the stiffness and the damping of the wall due to increased damage and cracking when subjected to seismic excitation is also highlighted in the paper.